Process of granulating commercial calcium-cyanamid powder.



A. DERGOLE.

PROCESS 0F GRANULATING COMMERCIAL CALCIUM OYANAMID POWDER.

APPLICATION FILED NOV. 12, 1908.

Patented Oct. 18,1910.

1 vantages areobviated by theuse of granu- 440 less than 25% andv not more than 35% or a 45 iron, aliiminum andcalcium are preferred,

n Y .lirmssacrona' DEncoLE, oriaoME, ITALY.

acacia.

'To all. whom *it may concern: Be it known that I, ANASSAGORA DER- COLE, a subject of the King of Italy, resi# dent of 32 Via Paolo Emilio, Rome, Italy, professor of chemistry, have invented a certain new and usefulProceSs of Granulating Commercial Calcium-Cyanamid Powder,

of which the following is a specification.

The use of commercial calcium cyanamid l0 in a powdered state asa fertilizer has Varions drawbacks, owing to its pulverulent condition and its contents of unslaked lime and calcium carbid. The fine powder is harmful both to the eyes and lungs and, bellsides, it is diicult to pack it in sacks, and when strewn in the fields, it is partly dis-- Vpersed by the wind. The sacks containing the powder zoften burst on account ofthe increase in the weight and volume of'A the powder caused by the hydration of the caustic lime due to atmospheric humidity. Finally, powdered calcium-cyanamid which commonly contains calcium phosphid, carbid and calcium oXid when in the ground causes development of acetylene which is obnoxious to the plants. All these disad- -lated calcium cyanamid.

My present invention has for its object to provide a process of granulating commercial calcium cyanamid powder and the newcom- -mercial product thereby obtained. A My new process substantially comprises the uniform wetting of calcium cya-namid powder witha material capable of reducingit from'a powdered to a granular condition, 7 after. which it is rapidly spread out in a very lthin layer, and then dried. The wetting may be done with water in a proportion not waterysolution ofmineral salts, or awatery solution of adhesive materials, eitheralone or in combination. As mineral salts, 'those of sodium, magnesium, .manganese, Azinc,

which are used in proporti adhesive liquids 1%-2% glue, gelatin, t starch,

on of 5%, and as solutlons of gum, albummous matenals,

casein, casemates, albuminates, etc., are used.V

The adhesive powderfmay be increased by the addition of van aluminum. salt such as alum, sodlu'm aluminate etc. l

Specification of Letters Patent.

Application led November 12, 1908. .Serial No.l 462,22Q.

ing circular disks provided with aluminum sulfate,

Patented oet. is, raro.

The purpose of `rapidly spreading out the moistened calcium cyanamid powder in Very thin layers is to lower the rapidly rising temperature ofthe product due to the action of water on the unslaked lime con-v tained therein, The heat otherwise generated would prevent granulation,and, more over, aloss of nitrogen by the decomposition ofthe calcium cyanamid would be causedaV For carrying outmy process, I .use an apparatus as shown on the annexed drawing, in whichl is the water-distributing tank, 2 a kneading apparatus, 3' a conveyer screw, et the drier, 5 -a screw for discharging the dried material, 6 the driving pulleys and. 7 an agitating'deviceoperated by the vertical shaft 8. f

The 'operation of the apparatus is asfollows.;- The calciumcyanamid powder is introduced into the knead'ng .apparatus 2, where it is moistened with a-sucient quantity of water. From the kneading appara-v tus'calcium cyanamid is transferred by the conveyer lscrew 3 into the drying apparatus 4, where it passes onto the agitating device 7, which consists in this case of nine rotat-l through which the material' reaches the screw 5, wherebyjit is d D nring its passage through :the drying' apparatus, the calciuml cyanamid is dried and continuously agitated, so ,that it will not ,agglomerate.` When the cyanamid reaches the gradually lscharged.

discharging screw*l 5, it l ispompletely dried andready I claim: v 4

A process of granulating commercial calcium v-cyanamid powder consisting in first uniformlywetting the powder with water .in a proportion not less than 25% and not more than 35%, thereby causing'the particles tov to be vlfilled into, boxes'or the like.

.adhere and then repeatedly spreading out vsaid particles into very thin l ingand granulating'fthef same. v

-In testimonyv whereof I vhavejaiixed my signature presence of twowitnes'ses;

' Witnesses: f `1 -4 v BAR'ronUz'zI ToMMAsso,

sav

ayers Yand dryy ANssAGoRa'DERcoLE; i 

